Can you be more specific as to which front engine seal? Crankshaft or Camshaft? Are they recommending replacing both? These should be replaced along with a timing belt replacement, how long has it been since the timing belt was replaced?

I had a friend fix the alternator, who works on cars often, and he believes it is the main crankshaft seal in the front. I have not owned the car very long, came to me with these problems, so I do not know when the timing belt was last replaced.

The timing belt should be replaced every 60,000 miles. If the belt was to break, engine damage will occur, so if there is any question, it's a good idea to replace the timing belt and all the front seals at the same time.
A shop will charge around 3 hours to replace the front crank seal, but I bet your friend is capable of performing this job.